64bit linux下JLINK V8+GDB环境配置

• 首先安装libusb和libreadline5;

        以ubuntu为例：

sudo apt-get install libusb lib32readline5

• 然后下载安装JLink_Linux_V422;

        地址为：        按照包中的README文档进行安装

cp -d libjlinkarm.so.* /usr/lib
ldconfig
cp 45-jlink.rules /etc/udev/rules.d/
groupadd plugdev                      // Creates new group "plugdev"
usermod -a -G plugdev       // Appends user  to the group "plugdev"

注意cp的-d选项，保留链接属性；还有最后的添加group完毕后，我仍然需要sudo才能执行start和JLinkGDBServer，否则出现Can not connect to J-Link via USB之类的错误，原因未查。

• 现在可以运行sudo ./start；

        第一次会更新JLink的firmware，然后会自动重启JLInk。
        CTRL+C关闭

• 启动GDB Server；

sudo ./JLinkGDBServer

        出现如下片段就说明成功：

SEGGER J-Link GDB Server V4.22

JLinkARM.dll V4.22 (DLL compiled Dec 17 2010 17:41:06)

Listening on TCP/IP port 2331

J-Link connected
Firmware: J-Link ARM V8 compiled Dec 16 2010 20:21:29
Hardware: V8.00
S/N: 68000019
Feature(s): RDI, FlashDL, FlashBP, JFlash, GDBFull

J-Link found 1 JTAG device, Total IRLen = 4
JTAG ID: 0x0032409D (ARM9)

• 安装GDB；

        交叉编译调试环境下需要安装类似arm-linux-gdb，如果你的交叉工具链已经包含gdb，则可以跳过这步了。
        如果用的是buildroot自己编译的交叉工具的话，记得make menuconfig选上

[*] Build gdb for the Host

        另外

Thread library implementation (linuxthreads) --->

        需要选为linuxthreads，否则编译过程会在linux-thread-db.c报错。

• 另开一个终端，启动GDB；

  arm-linux-gdb -x ~/work/gdb.cmd -ex "connect_jei 127.0.0.1 2331" /home/biu/work/u-boot-2014.01/u-boot

  其中gdb.cmd为一段用于初始化CPU之类的gdb命令。

        s3c2440的初始化可以参考：
        其他可以参考JLinkGDBServer文档UM08005_JLinkGDBServer.pdf来进行修改。
        运行结果如下：

GNU gdb (GDB) 7.5.1
Copyright (C) 2012 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "--host=x86_64-unknown-linux-gnu --target=arm-buildroot-linux-uclibcgnueabi".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /home/biu/work/u-boot-2014.01/u-boot...done.
warning: Unable to find dynamic linker breakpoint function.
GDB will be unable to debug shared library initializers
and track explicitly loaded dynamic code.
0x00000000 in ?? ()
Target endianess set to "little endian"
Expected an decimal digit (0-9)
Writing register (CPSR = 0x000000D3)
Select auto JTAG speed (8000 kHz)
Writing 0x00000000 @ address 0x53000000
Writing 0xFFFFFFFF @ address 0x4A000008
Writing 0x00007FFF @ address 0x4A00001C
Writing 0xFF000000 @ address 0x4C000000
Writing 0x00000005 @ address 0x4C000014
Writing 0x0007F021 @ address 0x4C000004
Writing 0x22111110 @ address 0x48000000
Writing 0x00000700 @ address 0x48000004
Writing 0x00000700 @ address 0x48000008
Writing 0x00000700 @ address 0x4800000C
Writing 0x00000700 @ address 0x48000010
Writing 0x00000700 @ address 0x48000014
Writing 0x00000700 @ address 0x48000018
Writing 0x00018009 @ address 0x4800001C
Writing 0x00018009 @ address 0x48000020
Writing 0x008E04EB @ address 0x48000024
Writing 0x000000B2 @ address 0x48000028
Writing 0x00000030 @ address 0x4800002C
Writing 0x00000030 @ address 0x48000030
(gdb)

• 调试程序；

        以uboot为例

(gdb) load

        就会把启动时最后一个参数指定的文件下载到开发板RAM中，下载地址为编译uboot的链接地址，GDBServer在下载完毕后还会把PC指向程序 首地址

Downloading 304 bytes @ address 0x33F80000
Downloading 304 bytes @ address 0x33F80130
Downloading 304 bytes @ address 0x33F80260
.
.
.
Downloading 128 bytes @ address 0x33FF9984
Downloading 17 bytes @ address 0x33FF9A04
Writing register (PC = 0x33F80000)

(gdb) l

        可以看到start.S的内容

(gdb) l
1    /*
2     * armboot - Startup Code for ARM920 CPU-core
3     *
4     * Copyright (c) 2001    Marius Gr?ger <[e-mail]>
5     * Copyright (c) 2002    Alex Züpke <[e-mail]>
6     * Copyright (c) 2002    Gary Jennejohn <[e-mail]>
7     *
8     * SPDX-License-Identifier:    GPL-2.0+
9     */
10
(gdb)
11    #include <asm-offsets.h>
12    #include <common.h>
13    #include <config.h>
14
15    /*
16     *************************************************************************
17     *
18     * Jump vector table as in table 3.1 in [1]
19     *
20     *************************************************************************
(gdb)
21     */
22
23
24    .globl _start
25    _start:    b    start_code
26        ldr    pc, _undefined_instruction
27        ldr    pc, _software_interrupt
28        ldr    pc, _prefetch_abort
29        ldr    pc, _data_abort
30        ldr    pc, _not_used

        然后就是具体的GDB调试过程了。

(gdb) break 117
Breakpoint 1 at 0x33f80064: file start.S, line 117.
(gdb) c
Continuing.

Breakpoint 1, start_code () at start.S:142
142        ldr    r0, =pWTCON
(gdb)

        参考链接：http://blog.csdn.net/samantha_sun/article/details/6245504
                            
                            等